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El complejo de búsqueda de homología eucariota distorsiona la estructura del ADN del donante para buscar homología

Mitchell V Woodhouse, Jingyi Hu, Meiling Wu

bioRxiv : the preprint server for biology

|September 5, 2025

Resumen

Las proteínas motoras Rad51 y Rad54 remodelan el ADN durante la búsqueda de homología para la reparación de la ruptura de doble hebra. Aplican fuerzas para controlar las interacciones del ADN, asegurando una selección precisa de la plantilla para la reparación genética.

Área de la Ciencia:

Biología molecular
La genética
La biofísica

Sus antecedentes:

La recombinación homóloga (RH) repara las rupturas de doble cadena de ADN utilizando una plantilla.
Las proteínas Rad51 y Rad54 son cruciales para la búsqueda de homología en eucariotas.
El mecanismo de aplicación de la fuerza durante la búsqueda de homología era previamente desconocido.

Objetivo del estudio:

Para investigar las fuerzas aplicadas por Rad51 y Rad54 en el ADN durante la búsqueda de homología.
Para entender cómo estas proteínas motoras remodelan las plantillas de ADN para su reparación.
Para aclarar el mecanismo de selección del objetivo en la reparación del ADN.

Principales métodos:

Pinzas magnéticas de una sola molécula.
Métodos de captura óptica.
Monitoreo de la remodelación de la plantilla de ADN durante la búsqueda de homología.

Principales resultados:

Rad51 y Rad54 remodelan el ADN del donante para regular las interacciones del filamento Rad51-ssDNA.
Tanto las fuerzas lineales (tensión) como las rotacionales (torsión) se aplican al ADN.
La procesividad de Rad54 es esencial para la selección de objetivos in vivo.

Conclusiones:

Rad51 y Rad54 coordinan para remodelar el ADN durante la búsqueda de homología.
Las proteínas motoras aplican fuerzas para sondear el ADN en busca de homología.
Este mecanismo es vital para una selección precisa de la plantilla de reparación del ADN.

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